pub trait AsyncFn2<Arg> {
type Output;
type Future: Future<Output = Self::Output>;
// Required method
fn call(&self, arg: Arg) -> Self::Future;
}Expand description
helper trait flatting tuple of arguments.
FromRequest trait extract a tuple of (type1, type2, type3, ..) from request type. this trait would destruct the tuple
handling over it to an async function use them as arguments.